Morphological dissociations in the L2 acquisition of an inflectionally rich language

This study investigates the validity of Pinker’s (1991, 1999) Dual-Mechanism Model in the mental representation of regular and irregular active past perfective verbs in adult non-native Greek. In this model, regular inflection is computed by a symbolic rule, while irregular words are fully stored in the lexicon. A nonce-probe elicitation task showed that both natives and non-natives generalized the regular affix -s, and more so in regular than in irregular perfective verb stems. Moreover, the degree of similarity of the nonce verbs to real ones did not affect the affixation of regulars. Dissimilar irregulars were affixed less often than similar ones by the intermediate learners but neither by the advanced learners, nor by the natives. Our findings support computation for regulars, as proposed by the Dual Mechanism Model, both in native and in non-native language acquisition. Yet, the model’s claim for full storage of all irregular words is not verified.